This invention relates to a method and apparatus for feeding a bale press. The invention is of particular importance, and hence is particularly directed to the packing of a bale press with waste material, such as waste fibers, in order to form bales of such material with the introduction of a minimum amount of dust to the atmosphere.
In mills wherein fibrous materials are handled, such as, for example, mills for producing cotton yarn and threads, the different processing equipment, such as combers, drawers, lappers, opening machines, pinking machines, and rollermatic machines, produce a certain amount of waste material. Some of the waste material may be recycled, and some of the waste material may be employed for other products, depending, for example, upon the staple length, dust content, etc. In any event, however, the disposal of the material will generally require packaging to a useable form, for example, bales.
The waste material may be expeditiously transported within a mill by means of permanently installed vacuum apparatus, so that the waste from the different machines or areas is automatically or semiautomatically directed to a central collection area. In this collection area the waste fibers may be directed into bins or trucks, with the waste material in each such container being identified preferably with respect to its origin, so that a proper disposition may be made of bales formed of such material.
In the past, it has hence been conventional to direct the material, for example, by manual feeding, from the bins or trucks to a bale press. Cotton fibers of the above type tend to be quite dusty, and the handling of the cotton fibers in this manner with the consequent agitation of the fibers, resulted in the release of large quantities of dust to the atmosphere. The working conditions in such manual loading facilities were therefore generally undesirable. Tests of the atmosphere in facilities of this type have shown in excess of 20 mg. per cubic meter of dust having particle sizes between 5 and 15 microns. The size of the dust particles is given in this example, since dust particles within this range of sizes are considered to be the most dangerous and to constitute a health hazard.
In addition to the health hazard resulting from the release of dust to the atmosphere, the manual loading of the bale presses also created a safety hazard, since it was necessary for the personnel in the facility to directly feed an partially pack the loose cotton fibers into the bale press.
Recently, standards have been established for the quality of air in mills of this type. More specifically, the Office of Safety and Health Administration has established a standard, whereby personnel without breathing apparatus such as filters may not work full time in facilities having more than 1 mg. of dust per cubic meter, of a size in the range of 5 to 15 microns. In view of the large quantities of dust which are present in cotton fiber waste materials, this standard has been especially difficult to meet, and, at least up until the time of the present invention, it is believed that no practical solution has been found for the problem.
As an example, in studies leading to the present invention material handling fan devices were employed to pick up the cotton waste from the trucks, and direct it to the press. This solution was unsatisfactory, since it did not result in an adequate reduction of dust in the atmosphere, and produced the additional undesirable results that an excess amount of air was directed into the bale press. In a further attempt to solve the problem, the manual feeding of the press was eliminated by directing the waste fibers from the storage bins or trucks to the bale press by gravity, with screens being provided to avoid build-up of air. This solution was also unsatisfactory, since the dangerous dust being of a small particle size, readily passed into the atmosphere of the facility.
In still further attempts to solve the problem, the cotton waste was directed to sets of dust bags, but this solution also resulted in the generation of too much dust in the facility. Still further, a condenser, of the type employed in the mill, was modified to collect the waste fibers from the storage bins, with the cotton fiber from the condenser being discharged to the bale press. This solution was also unsatisfactory, since the output of a condenser is fluffy, and as a consequence an adequate amount of cotton fiber could not be fed to the press before raising of the ram of the press, so that excessive operation of the bale press ram was necessary.
It is therefore apparent that it is difficult to adequately reduce the dust content of the atmosphere in a bale press feeding facility for packing fibrous materials, such that the dust content of the air in the packing facility be reduced below the 1 mg. per cubic meter standard.
The present invention is consequently directed to a method and apparatus for solving this problem.
Briefly stated, in accordance with the invention, a condenser of the above discussed type is employed to form a blanket from the waste material. In one arrangement in accordance with the invention, an operator may be employed to manipulate the input pipe of the condenser in a bin or storage truck, although automatic equipment may be alternatively employed for this purpose.
The inner output of the condenser may be directed to a conventional filter, for removal of dust. The filter may of course advantageously be positioned externally of the mill, so that the dust which may be released by the condenser is not recirculated in the mill.
As discussed above, the fiber blanket output of a conventional condenser is fluffy, and cannot be employed to properly feed a bale press. Consequently, in accordance with the invention, the blanket is passed through rolling devices of successively decreasing clearance, whereby the thickness of the blanket is reduced and its density is consequently increased. In addition, in accordance with the invention, the precompressed blanket may be further compressed by conveying it on a conveying belt to the bale press through a chamber of gradually reduced height. The chamber thus serves the function of confining all dust particles, while enabling still further compression of the blanket. It is of course to be understood that the remainder of the processing equipment of the invention is also sealed in a dust-tight manner, to avoid release of dust particles in the range of 4 to 15 microns.
The bale press has a loading door which is angularly disposed at the outlet of the conveyor belt, so that the compressed blanket is fed directly into the bale press. In accordance with the invention, the blanket thus fed to the bale press is packed by means of a hydraulically operated foot extending downwardly through the bale press loading door opening, the packer preferably being operated cyclically in response to the presence of waste fibers to be packed. Specifically, the chamber is provided with a hinged portion at its outlet, so that a switch cooperatively positioned with respect to the hinged portion is actuated by the passage of water fiber thereunder. Operation of the switch, which is therefore responsive to the presence of waste materials to be loaded, may therefore be employed to initiate the cyclic operation of the packer through a determined number of cycles.
When the bale press is fully loaded, it may then be operated either manually or automatically to form the desired bales of material for shipping or other disposal, in a conventional manner.
The method and apparatus in accordance with the invention thereby enables either the complete or substantially complete automatic handling of the waste material, so that manual handling operations are no longer necessary. If an operator is employed, the operator need only direct the inlet suction pipe to the condenser. The method and apparatus in accordance with the invention have been found to thereby substantially reduce the amount of dust in the bale press facility, so that the standard of 1 mg. per cubic meter can be met.